Retrofit Trailer Hitch Wiring Harness - AN31.19-P-8100-05MFC
Model 118.3
| Topical note | Notes on the use of paint scraping nuts on ground connections | AH00.19-P-1000-20A | |
| Topical note | Notes on retrofitting electrical/optical lines | AH82.00-P-0000-01A | |
| Topical note | Information on preventing damage to electronic components due to electrostatic discharge | AH54.00-P-0001-01A | |
| Notes on safety-relevant components | AH00.00-Z-0019-01A |
| Number | Designation | Model 118 | |||
|---|---|---|---|---|---|
| BA00.19-P-1009-02E | Right wheelhouse trunk ground point | W7 | M6 | Nm | 10 |
Connection scheme
Routing diagram shown on left-hand drive vehicle
The routing of the control unit wiring harness (22) is shown on a left-hand drive vehicle. The control unit wiring harness (22) on right-hand drive vehicles is routed on the right side of the vehicle toward the front and from there under the removed instrument panel to the central control unit (N10).
- Remove all fasteners on control unit wiring harness (22).
The fasteners are no longer required.
- Route brown line (BN) to right wheel arch trunk ground point (W7).
- Bend shackles (arrows) at round cable lug (22.9) and remove nut.
- Turn round cable lug (22.9) and connect to right wheel arch trunk ground point (W7).
The side of the round cable lug (22.9) on which the nut was fastened must face downwards.
A maximum of 4 round cable lugs may be connected per ground point. If already occupied, select another ground point that has not been used.
- Attach black 6-pin contact socket (22.1) of control unit wiring harness (22) to trailer recognition control unit (N28/1).
- Attach black 10-pin contact socket (22.2) of control unit wiring harness (22) to trailer recognition control unit (N28/1).
- Attach white 10-pin contact socket (22.3) of control unit wiring harness (22) to trailer recognition control unit (N28/1).
- Route trailer hitch switch branch-off line (22.8) of control unit wiring harness (22) on right trunk lid hinge to installation location of trailer hitch switch (S143/3).
- Fix trailer hitch switch branch-off line (22.8) in place with cable ties.
The black 6-pin contact socket (22.6) is connected to the trailer hitch switch (S143/3) at a later stage.
- Remove black 20-pin contact socket insert from white 20-pin contact socket (22.4).
- Remove electric lines of black 20-pin contact socket insert and note down contact cavity assignment.
Contact cavity assignment:
Contact cavity 1 = Black/white line
Contact cavity 7 = Brown line
Contact cavity 11 = Pink/red line
Contact cavity 17 = Brown/red line
Take appropriate tool from the
basic wiring harness repair kit or the
- Route central control unit branch-off line (22.5) of control unit wiring harness (22) into footwell in rear passenger compartment on front passenger side.
- Route central control unit branch-off line (22.5) into front passenger footwell.
- Route central control unit branch-off line (22.5) to central control unit (N10) and fix in place with cable ties along its entire length.
- Remove white 20-pin contact socket (41) from central control unit (N10).
- Remove black 20-pin contact socket insert (41.1) from white 20-pin contact socket (41).
- Install electric lines of central control unit branch-off line (22.5) into black 20-pin contact socket insert (41.1) as noted previously.
Contact cavity assignment:
Contact cavity 1 = Black/white line
Contact cavity 7 = Brown line
Contact cavity 11 = Pink/red line
Contact cavity 17 = Brown/red line
- Install black 20-pin contact socket insert (41.1) into white 20-pin contact socket (41).
- Attach white 20-pin contact socket (41) to central control unit (N10).
- Route red/green line (RD/GN) and black fuse holder (22.7) with lines to installation location of rear fuse and relay module (F152/2) and fix in place using cable ties.
- Install red/green line (RD/GN) and black fuse holder (22.7) into rear fuse and relay module (F152/2).
Remove black fuse holder (22.8) from parts kit.
- Clip rear fuse and relay module (F152/2) into cutout.
- Fix control unit wiring harness (22) in place with cable ties.